Gear-grinding machine



1929- o. G. SIMMONS 1,731,505

GEAR GRINDING MACHINE Filed March 15, 1928 5 Sheets-Sheet 1 INVENTOR:

Oct. 15, 1929. O G SIMMONS 1,731,505

' GEAR GRINDING MACHINE Filed March 15, 1.928 3 Sheets-Sheet 2 INVENTOR Oct. 15, 1929. sl N 1,731,505 I GEAR GRINDING MACHINE Filed March 13, 1928 3 Sheets-Sheet 3 w N Q I INVENTOR 1 Patented Oct. 15, 1929 UNITED STATES PATENT OFFICE OLIVER G. SIMMONS, OF LAKEWOOD, OHIO GEAR-GRINDING MACHINE Application filed March 13, 1928. Serial No. 261,235.

98,791, filed March 31st, 1926.

In grinding gear shaper cutters it is preferable to cause the rectilinear movement of the work spindle to reverse. itself at'a premove a certain amount of metal from the tops 1 of the teeth of the gear cut by the gear shaper cutter, thus modifying the involute form of tooth from the desired involute, the modified curve taking the form of an epitrochoid. The teeth of a gear produced by such a cutter is well known in the art and is referred to as a gear in which the teeth have been eased-01f. This is done to prevent interference when the teeth of a gear are relatively long and the pressure angle is small as a compromise to compensate for slight inaccuracies in the gear teeth which have been introduced as mechanical errors of workmanship or errors of hardening introduced during the process of heat treating the gear. It is said, that gears provided with eased-off teeth as described per- 0 mit greater tolerance limits of error. Gears made with eased-0E teeth, therefore, do not have what is known commerciall as a full tooth hearing. The bearing, it is o vious, will be held to a point some distance below the top of the toothof the gear, and the magnitude of the measure of this is dependent upon the amount of flank fullness in the gear shaper cutter previously referred to. The measure of the flank fullness of gear shaper cutters 59 being controllable, it is obvious that any February 14:, 1928, Serial No. 131,885, filed August 27, 1926, Serial No. 150,865, filed Nokindred articles of manufacture.

mechanism comprising means of adjustment which will function while the machine is in operation is preferable. Means containing mechanism for functioning in machines as referred to have been proposed heretofore by the applicant in pending application for Letters Patent above referred to and other copending applications, Serial No. 125,369, filed July 28, 1926, Patent No. 1,659,37 9, granted vember 26, 1926, Patent No. 1,662,589, granted March 13, 1928, and others. A main object of the invention, therefore resides in the means for causing a workcarrying spindle to oscillate on its axis and to reciprocate bodily along a line perpendicular to the axis of said spindle and to control the position of reverse of said reciprocal movement by the movement of a cooperating member, which is operable to effect the adjustment independently of the movement of the work spindle.

Other objects of the invention reside in the means for swivelling the plane of the recip- 'rocal movement of the spindle and its cooperating members so that the present invention will function as herein described at any given pressure angle at which the machine contain ing this invention is designed to be adjustably positioned Within range of its capacity.

A further object of the invention is toprovide adjustable correlated mechanical means for machines adapted to generate the curved teeth of gears, gear shaper cutters and all A still further object of the invention resides in providing the work-carrying spindle with a gear (preferably a master gear) fixed- 1y secured thereto, a swivelling member adapted to carry a movable member, one part of which is in the form of a yoke adapted preferably to carry a rack member, the teeth 'of which intermesh the teeth of the gear, an end extension on said yoke member adapted to be journalled in an end portion of a slide, means to position said yoke member in a plane parallel to the plane of rectilinear movement of said slide, means to fixedly secure said yoke member in said adjusted position,means to angularly adjust swivel member upon which is means.

mounted the aforesaid slide to an angle equal to the complemental pressure angle with respect to the face of the cutting element, means to angularly adjust said cutting element about,

a vertical center linev to the angle of the helix of the teeth of the work and means to cause an oscillating movement to said work spindle or rectilinear movement to said slide, or a movement combining each, but preferably oscillating movement to said work spindle whereby said Slide is caused to reciprocate uniformly or non-uniformly as the oscillating movement of thework spindle is uniform or non-uniform.

With the the above and still other objects in View the invention comprises a workcarrying spindle, means to simultaneously reciprocate and oscillate said Work spindle, and means connected therewith controlling the position of reverse of said reciprocating motion to produce flank fullness or non-flank fullness in gears and gear sbaper cutters as illustrated in the accompanying drawings hereinafter described and particularly set forth in the appended claims, together with such variation and modification as will be apparent to those skilled in the art to which the invention appertains. Reference should be made to the accompanymg drawings forming of this invention to awell known gear grinding machine.

Fig. 2 is a plan view partly in fragmentary section of the present invention.

Fig. 3 is a top plan view of the machine.

The numeral 1 indicates the bed of the machine upon which is mounted upright swivel base 2. The upright 3 is adapted to engage the slide on swivel base 2 through the medium of the V.-guide-ways, not shown, by means of the screw 4 having threaded engagement with the swivel base 2, the hand wheel 5 being secured to said screw 4. The adjustable vertical slide 6 is adapted to engage V-ways 7 on upright 3. The cutting element 8, which may be an abrasive heel or a milling cutter, is carried by a spindle in the slide 6. The cutting element 8 may be rotated by any suitable Swivel member 9 is adjustably mounted on a bearing carried by the bed 1. Slide 10 engages V-guide-ways on swivel member 9 and is adapted to move in a'rectilinear path thereof. The end-plate 11- is secured to the left end portion of the slide 10 x to which is fixedly secured'the eye-bolt 12, 3 through which the cable 13 is passed and secured. The other end of the cable 13 is attached to a weight which causes slide 10 to exert constant force in one direction indicated by the arrow 14. The work spindle 15 is journalled in a portion 16 of the slide 10. The gear 17 is fixedly secured'to work spindle 15 and heldin said .being fixedly secured to and carried by the yoke 23 by means of the fillis'ter head screws 24 and 25 passing through said rack and having threaded engagement with said yoke. The yoke member 23 is provided, preferably at'the left hand end thereof of the person viewing the drawing, Fig. 1, with the shaft extension 26 which is adapted to be journalled and reciprocated in the extension 27 of the slide 10, whereas the right hand end 28 of said yoke 23 is preferabl fixedly secured to the adjustably positione spindle 29, said-spindle 29 being carried by the tailstock member 30, said tail stock member 30 being provided with an end flange 31 in which is journalled tail stock screw 32, one end of which screw 32 has threaded engagement with nut 33 fixedly secured to spindle 29, one end of which screw is adapted to receive the hand wheel 34 by any suitable means, preferably by means well known in the art, so that as hand wheel 34 is rotated, spindle 29 and yoke 23 will be moved to the right or to the left of the person The rack 20 viewing the drawing, Fig. 1. This movement rectilinear movement of slide 10 or absence of said movement of slide 10. If, however, work spindle 15 is restrained from rotary movement, then the movement of yoke 23 as described will result in efl'ect-ing a bodilyrectilinear movement of slide 10, yoke 23 and component members carried by the yoke and spindle as described and, vice versa, if the.

slide 10 is restrained from movement as referred to there will be a rotary movement only of work spindle 15 if the yoke 23 is moved as described.- Either members, 10 or 15, may be restrained as referred to. In the practice of my invention, however, I prefer to restrain the work spindle and move the members aforesaid as aunitary part when yoke 23 is moved as described. However, in the practice of this invention it is immaterial which member is restrained in the aforesaid movementof the yoke 23, and since it is not necessary to restrain both movements in the movement aforesaid, one only being necessary, it is obvious in the embodiment of the inventionin a machine, for the purpose of this specification that one member be selected as a restraining. member. I have, therefore,

preferably selected to restrain the work spin.- dle 15, although in the practice of my invention I could just as easily and by the same line of reasoning select the member 10 as the member to be restrained in the movement of the yoke 23. The choice is influenced by the necessity of describing the application of this invention to one of several well known grinding machines. I will describe briefly, therefore, one well known machine in which the spindle is adapted to be restrained in the movement of the yoke 23, but it must be understood that my invention is not limited to gear grinding machines in which the work spindle is restrained from movement, because the invention is adaptable for use in gear grinding machines in which the slide 10 is restrained from movement and the application of this invention to such machine could be made just as readily. It will appear later by restraining the movement of work spindle 15, or slide 10, that it merely resolves itself to a question of Whether in the functional operation of gear grinding machines the rota-- tion of the spindle causes the slide to move,

or whether by moving the slide the spindle is caused to rotate. In the former, power is applied to the spindle and in the latter, the

power is applied to the slide as is well known in the art.

Tail stock member 30 is preferably pro vided with lever arm 35 which is adapted to fixedly secure tail stock spindle 29 in the usual way well known in the art. The tail stock member 30 is preferably provided with the yoke portion 36 which yoke portion surrounds slide 10 and is fixedly secured to swivel member 9 by means of the bolts 37 so that as swivel member 9 is adjusted to the pressure angle of the gear or gear shaper cutter to be ground, the connected members including slide 10, tail stock member 30 and yoke 23 will be swivelled as a unitary part.

If the work spindle 15 is given rotary motion, uniform or non-uniform, the gear 17 intermeshing with rack 20 will cause slide 10 to move and if the rotary movement of the work spindle 15 is in the form of an oscillating movement, the slide 10 will be caused to reciprocate to and fro on the swivel 9,- and if the movement of the work spindle 15 is uniform then the movement of the slide will be uniform, and, Vice versa, if the movement of the work spindle is non-uniform the movement likewise of the slide will be non-uniform, and the magnitude of the movement, whether it be uniform or non-uniform, is dependent upon the pitch diameter of the gear 17 for example, if the pitch circle of the gear 17 has a perimeter measure of sixteen inches, the slide will move sixteen inches if the gear 17 is given one turn and in direct ratio thereto for any fraction of a turn.

One end portion of the cable 13 being secured to the end portion of the slide 10, having a weight attached to the other end of said cable 13, will cause slide 10 to move in the direction of the arrow 14 to a position of rest, taking up all lost motion if any exists in any of the connecting parts. When force is applied to oscillate the work spindle 15, slide 10 is actuated to move to lift the weight at the end of the cable 13, and when the motion of the work spindle is reversed to the opposite direction the weight, nevertheless, continues to exert its force in the same direction so that in the functional operation of the means here in disclosed, as applied to a grinding machine of the character set forth, will cause a given point on the work spindle to travel in a true geometrical path for the reason the weight on the end of the cable 13 exerting constant force always in one direction will keep the slide 10 to its lowermost position to the right of the person viewing the drawing, Fig. 1, this force component, as stated, being constant will cause the work spindle 15 to exert a constant rotative force in the direction of the arrow 38, and this force will be overcome by the positive mechanical means applied to the work spindle 15 through the medium of members of the connecting rod 39 and hell crank 40, in the application of the present invention to the machine referred to.

If now, the machine is operating and the work spindle oscillating and the slide reciprocating as described, it is obvious that an additional independent rectilinear movement will be given to the slide 10 if the hand wheel 34 is rotated. The object of this independent movement to the slide 10, which is a movement of adjustment for positioning the side of a tooth of the work relative to the cutting element for the purpose of controlling flank fullness, or absence of flank fullness in gear shaper cutters or the like, as previously referred to, and fully set forth in copending application. for Letters Patent herein referred to. Flank fullness, therefore, in anygear shaper cutter and the like is controlled in the present invention by the relative movement of slide 10 with respect to the fixed position of the cutting element 8, and if no flank fullness is required, it is only necessary to allow the slide 10, which carries the work spindle 15,.to move further to the right of the person 8 viewing the drawing, Fig. 1. This is accomplished as stated by turning hand wheel 34 to eifect the adjustment referred to. If, however, fiank fullness is required it is merely necessary to cause slide 10 to reverse its movement, and return to its former position before the center 0, of the work spindle 15, coincides with the cutting face C, of the cutting element 8. The position of the axis 0, therefore, to the cutting face C, is controlled by the position of the tail stock spindle 29.

In grinding gears, gear shaper cutters and the like which may have hehcally arranged teeth, it is necessary to swivel the cutting element 8 about a vertical axis coincident with the cutting face C. This is provided for by means of the swivel upright base 2. Th1s may be swivelled on bed 1, in a plane perpendicular to the plane ofthe sheet of drawing, Fig. 1, to any desired angle of helix corresponding to a desired helical angle of the teeth of gears or gear shaper cutters and in the case of the latter it may be swivelled to a slightly greater the machine referred to, wherein a swivel member 9 is disposed to the pressure angle desired in the gear, when operating on the moulding generatmg principle of action, to

the end that the cutting face C of the cutting element 8 with the sliding ways W of the slide 10, form an angle equal to the complemental pressure angle desired in the cutters,

or gears. It is only necessary, therefore, where the pitch diameter remainsfixed, to obtain a definite pressure angle in a gear or cutter, to merely adjust swivel 9 tothe desired angle of pressure. This is accomplished by any suitable means, for example, means illustrated and described in my copending application, Serial No. 98,791, filed March 31, 1926, previously referred to. If, however, it is desired to operate on the describing generating principle of action, the slide 10 will be adjusted to zero pressure angle, that is to say, the cutting face C, of the cutting element 8, will be normal to and form an angle of substantially 90 degrees with the sliding ways W of the slide 10, and when so adjusted the pitch circle of the gear becomes the base circle of the tooth curves of the work, and the face C, of the cutting element 8, will generate true involute curves in the teeth of gears and the like, having the pitch circle of the gears 17 as a base circle. This must not be confused with the pitch circle of gears 17 when operating on the molding generating principle of action, in which the slide 10 is disposed with swivel member 9 to the angle of pressure as previously described. The two principles of actlon herein referred toare well known to those skilled in the art and are fully set forth in my copending application for Letters Patent, Serial No. 131,885, previously referred to.

Having thus described my invention, I claim:

l In a machine of the character set forth, a slide, a guide-way for the slide, a work spin .dle on the slide, a gear fixed to the spindle, a

yoke partially surrounding said work spindle, arack fixedly secured to said yoke inter-- meshing with said gear, means for oscillatmg said spindle and means for moving the; yoke along the guide-way and for securing the same in adjusted positions with respect thereto. a

2. In a machine of the character set forth, a slide, a guide-way for the slide, a work spindle on the slide, and a gear fixedly secured thereto, a yoke which partially surrounds said work spindle, a rack fixedly secured to said yoke and intermeshing with the teeth of the gear, the slide carrying said work spindle mounted upon a swivel member, a cutting element and means to angularly adjust said swivel member and said cutting element to the complemental angle of pressure, means for oscillating said spindle and means for adjusting said yoke along said guide-way.

3. In a machine of the character set forth, a work spindle, a slide carrying the work spindle, a swivelling member carrying the slide, a gear fixedly secured to said spindle, an adjustable yoke which partially surrounds said work spindle, -a rack fixedly secured to said yoke and intermeshing with the teeth of the gear, an adjustable tail stock spindle connected to said yoke, a tail stock member carrying said yoke, having a portion straddling the slide carrying said work spindle, said portion being fixedly secured to a swivelling member carrying said slide, and means to position said yoke member with respect to said tail stock member whereby the flank fullness of the teeth of gear shaper cutters is controlled as set forth.

4. In a machine of the character set forth, a slide, a guide-way for the slide, a work spindle on the slide, a gear fixedly secured to the spindle, a yoke partially surrounding said work spindle, a rack fixed to said yoke and intermeshing with said gear, means for oscillating .said spindle, means for moving the yoke along the guide-way and for securing the v same in adjusted positions with respect thereto, a cutting element, and means to angularly adjust the face of the cutting element with respect to the axis of said spindle.

5. In a machine of the character set forth, a work carrying spindle with a gear fixedly secured thereto, a swivelling member adapted to carry a movable member, one part of which is in the form of a yoke adapted to carry a rack member, an end extension on said yoke'member adapted to be journalled in an end portion of a slide, means to position said yoke member in a plane parallel to the plane of rectilinear movement of said slide, means to fixedly secure said yoke member in said adjusted position, means to angularly adjust swivel member on which is mounted the aforesaid slide to an angle equal to the complemental pressure angle with respect to the face of a cutting element, means to angularly adjust said cutting element about a vertical center line to the angle of helix of the teeth of the work, means to cause an oscillating movement to said work spindle or a rectilinear movement to said slide, whereby said slide is caused to reciprocateuniformly or non-uniformly as the oscillating movement of the work spindle is uniform or non-uniform.

6. Ina machine of the character set forth, a work carrying spindle, a gear fixedly secured thereto, a swivelling member adapted to carry a movable member, one part of which is in the form of a yoke partially surrounding said work spindle, a rack having intermeshing engagement with a gear and fixedly secured to said yoke, an end extension on said yoke member adapted to be journalled in an end portion of a slide, means to position said yoke member in a planeparallel to the plane of rectilinear movement of said slide, means to fixedly secure said yoke member in said adjusted position, means to angularly adjust swivel member upon which is mounted the aforesaid slide to an angle equal to the com- I plemental pressure angle with respect to the face of a cutting element, means to angularly adjust said cutting element about a vertical center line to the angle of the helix of the teeth of the work, means to cause an oscillating movement to said work spindle or a rectilinear movement to said slide, preferably oscillating movement to said work spindle,

movements to the slide at speeds proportional to the angular speeds of the work spindle. Signed this 12th day of March, 1928.

OLIVER G. SIMMONS.

whereby said slide is caused to reciprocate uniformly as the oscillating movement of the work spindle is uniform or non-uniform.

7. In a machine of the character set forth, a slide, a guideway r the slide, a transversely disposed work sp ndle on the slide, a yoke partially surrounding the work spindle, means for moving the yoke along the guideway and for securing the same in a diusted positions with respect thereto, means for oscillating the work spindle, and means inter posed between the yoke and work spindle for imparting linear movements to the slide at speeds proportional to the angular speeds of the work spindle.

8. In a machine of the character set forth, a supporting member having a guideway, a slide mounted for movement in the guideway, a transversely disposed work spindle on the slide, a yoke partially surrounding the work spindle, said yoke having bearing portions at the opposite ends thereof parallel with the guideway, a bearing for one of said ends carried by the slide, a bearing for the opposite and carried by the supporting member, means associated with the last mentioned end of the yoke for adjusting the yoke along the guideway and for securing the same in adjusted positions, means for oscillating the work spindle, and means interposed between the yoke and guideway for imparting linear 

